Slip



Dec. 8, 1936. 1 F, BAASH' 2,063,361

SLIP

Filed June 2, 1956 Z'Sheets-Sheet 1 Z755 Haya/'27g Patented Dec. 8, 1936 stares ement OFFICE 16 Claims.

This invention relates to well drilling equipment and relates more particularly to slips for use in the rotary table of a well drilling rig. A general object oi this invention is to provide practical effective and improved slips.

Another object of this invention is to provide improved slips that are adapted to automatically obtain full uniform engagement with the pipe or object handled.

Another object of this invention is to provide slips embodying shiftable or rockable gripping elements and novel means for assuring the proper Contact of the gripping elements with the pipe whereby they automatically rock into full balanced engagement with the object or pipe.

Another object ci this invention is to provide slips oi the character mentioned embodying self-adjusting and self equalizing gripping elements and i .eans normally resisting or overcoming the action of gravity on the gripping elements whereby their upper portions, instead of their lower portions, have initial contact with the pipe so that the elem-ents obtain complete gripping engagement with the pipe.

Another object of this invention is to provide slips of the character mentioned wherein the handles for lifting and manipulating the slips are connected with the rocking gripping elements to effect their proper initial engagement with the pipo upon the insertion of the slips in the rotary table bushing.

Another object of this invention is to provide slips of the character mentioned in which the shiftable or rockable gripping elements obtain full uniform engagement with the pipe whereby the gripping forces are evenly distributed on the pipe and do not cause crushing or scoring of the pipe.

A further object of this invention is to provide improved slips of the character mentioned in which the grip-ping elements do not require special manual adjustment or attention when the slips are inserted in the rotary table bushing.

Another object of this invention is to provide slips of the character mentioned that are inexpensive and that are easy and convenient to manipulate.

The various objects and features of my invention will be fully understood from the following detailed description of typical preferred forms and applications of the invention, throughout which description reference is made to the accompanying drawings, in which:

Fig. 1 is a top or plan View of a set of slips provided by the invention showing them in posi,-

(Cl. 24a-263) tion in a rotary table bushing in engagement with a pipe. Fig. 2 is an enlarged longitudinal detailed sectional view of one of the slips with a portion of the handle broken away.' Figs. 3 and 4 are horizontal detailed sectional views taken as indicated by lines 3--3 and 44, respectively, on Fig. 2. Fig. 5 is a plan elevation of another form of the slips of the invention showing them in the operative position in a rotary table bushing, and Fig. 6 is a side elevation of one of the slips illustrated in Fig. 5 removed from the bushing being a View taken substantially as indicated by line 6 5 on Fig. 5.

The slips provided by this invention are adapted to be employed in the bushing of a rotary table to grip a pipe, a string of pipe or, a similar object extending through the table. It is the common practice to provide the bushing of a rotary table with a central downwardly and inwardly tapered opening for receiving slips and the like. Fig. 1 of the drawings illustrates a portion of a bushing B and shows three typical slips S of the present invention arranged in the opening O of the bushing B to grip a pipe P. The invention contemplates the provision of slips of various sizes and in sets having Various numbers of slips. Accordingly, the invention is not to be construed as limited to the employment of three slips, as illustrated in Fig. 1, and is not to be construed as limited to the specific details about to be described.

As the three slips S illustrated in Fig, 1 of the drawings may be identical I will proceed with a detailed description of one slip S it being understood that such description is equally applicable to the other slips.

The slip S of the form of the invention illustrated in Figs. 1 to 4, inclusive, of the drawings includes, generally, a body Il) intended for .arrangement in the opening O of the bushing B, a shiftable or rockable gripping element Il carried by the body lll for gripping the pipe P and means l2 operable to automatically condition the gripping element Il for initial engagement with the pipe P to obtain extensive uniform engagement With the pipe.

The body l 0 is a wedge-like structure or member adapted to be inserted in the opening O to bring the gripping element I l in cooperation with the pipe P. In practice the body lll is preferably integral as illustrated. The body IIJ has a down- Wardly and inwardly inclined and transversely convexed outer surface I3 for cooperating with or fitting against the inclined wall of the opening O. The body Hl is preferably proportioned to project above the top of the bushing B when in proper position in the opening O. The upper end I4 of the body I9 may be flat and substantially horizontal. The lower end I5 of the body I0 may be flat and horizontal and the surface I3 may terminate at its lower end in a face I6 pitched at a greater angle to the vertical than the surface I3. The body I!! maybe provided with internal charnbers I1 to be light in weight.

In accordance with the invention a socket or recess I3 is provided in the inner side of the body ill to carry or receive the gripping element II. 'I'he inner surface I9 of the body I may be cylindrically concaved to have suitable substantial clearance with the pipe P when the slip is in the operative position in the bushing B'. The recess I8 extends inwardly from the surface I9 and is shaped to provide for or allow rocking movement of the gripping element II about a substantially horizontal axis. The inner wall `2l! of the recess I8 is preferably concaved and is preferably cylindrically curved about a transverse or horizontal axis. TheVop-posite side walls of the recess I8 may be ilat and vertical. The recess I8 is of substantial extent having its upper and lower ends adjacent the upper and lower ends of the body I0. The wall 29 extends throughout the length of the recess I 8 and has its upper and lower ends at the inner surface I9 of the body.

The gripping element I I is arranged in the recess IS to project from the inner surface I9 of the body Il! for the purpose of contacting and gripping the pipe P. In accordance with the invention the gripping element I I is capable of limiting rocking movement about a substantially horizontal axis to properly conform to and evenly ear on the pipe P. The opposite side surfaces 2l of the gripping element I I may be flat and vertical and may have working or sliding engagement with the side walls of the recess I 8. The inner surface 22 of the gripping element II is cylindrically convexed to conform to and move on the wall 29. The surface 22 is cylindrically curved about a substantially horizontal axis and has even extensive bearing engagement with the wall 29 of the recess I8. The gripping element II is proportioned to project from the inner surface I9 of the body IB and its active or inner side is concaved to conform generally to the pipe P.

The projecting portion of the gripping element i I is provided with means for gripping the pipe P. In the particular case illustrated the gripping element II is integral and the gripping means is in the form of integral teeth 23 on the active side of the element, it being obvious that the gripping element may have a replaceable toothed liner for contacting the pipe P, if desired. The teeth 23 are curved to nt about the pipe P and are shaped to grip the pipe for the purpose of supporting the same. It is believed that it will be apparent how the cylindrically curved surface 22 engages the concave wall to allow rocking movement of the gripping element II about a substantially horizontal axis. Means is provided for limiting this rocking movement of t e element I I. In the simple form of the invention illustrated this stop means comprises a vertically elongated opening 24 extending transversely through the central portion of the gripping element I I. A pin 25 extends through the opening 24 and has its opposite end portions supported in horizontal openings 2B in the body il?. The ends of:A the opening 24 are adapted to cooperate with the pin 25 to limit the rocking or shifting of the gripping element I I in the recess I8.

The means I2 is provided to automatically condition the element II for cooperation With the pipe P so that the upper teeth 24 have initial engagement with the pipe. In the preferred ar'- rangement illustrated the means I2 also constitutes a handle means to facilitate the handling and manipulation of the slip S. The means I2 includes a link or rod 21 pivotally connected with the gripping element II. A vertical opening 28 extends into the upper portion of the gripping element II and registers with a vertical opening 29 in the upper end part of the body I0. The rod 21 extends vertically through the openings 28 and 29 and its lower end is pivotally connected with the gripping element II. 'Ihe lower portion of the rod 21 may be enlarged and provided with an opening 30. A pivot pin 3l extends through the opening 30 and is supported in transverse openings 32 n the body I0 to pivotally secure the rod 21 to the element II. The rod 21 extends through the openings 28 and 29 with substantial clearance to permit the desired rocking movement of the gripping element II.

The rod 21 extends beyond the upper end I4 of the body I0 and is provided at its upper e'nd with a bifurcated or yoked head 32. A washer 33 surrounds the rod 21 and bears against the upper end I4 of the body I0 around the upper end of the opening 29. The means I2 includes a spring 34 for yieldingly holding the gripping element II in an up position, that is a position where its inner side is slightly inclined downwardly and outwardly as illustrated in Fig. 2 of the drawings. The spring 34 surrounds the projecting portion of the rod 21 and is arranged under compression between the head 32 and the washer 33. The spring 34 exerts an upward force on the rod 21 to urge the gripping element II to the inclined position shown in Fig. 2 of the drawings where its upper teeth 23 are adapted to have initial engagement with the pipe P.

The means I2 may include a handle for facilitating the handling and manipulation of the slip S. In accordance with the broader principles of the invention this handle may be of various constructions and designs. The particular handle illustrated in the drawings comprises a stem 35 and a loop-like head 38 on the outer end of the stem adapted to be grasped. The stem 35 of the handle may be pivotally connected with the rod 21 so that the act of lifting the slip S and inserting the slip in the opening O by means of the handle definitely moves and holds the gripping element II in its up or inclined position shown in Fig. 2 of the drawings. The inner end portion of the handle stem 35 enters between the tines or arms of the yoked head 32 and a pivot pin 31 passes through openings in the yoked head 32 and the stem 35 to pivotally secure the stem to the head. The head 36 of the handle may be provided with a depending rest or stop 38 for engaging the upper surface of the bushing B or the rotary table to support the head above the bushing or table where it may be conveniently grasped.

When the slips S are to be employed they may be lifted by means of the above-described handles and individually inserted in the opening O so that their gripping elements II are brought into wedging and supporting contact with the pipe P. As above described, the gripping element II of a slip S is normally held in its up position by the spring 34 and when in this up position the inner side of the gripping element is slightly inclined downwardly and outwardly, as best illustrated in Fig. 2 of the drawings. The lifting and insertion of the slip S by the handle puts an up strain on the rod 21 to denitely hold the gripping element II in this up position. Thus when a slip S` is inserted in the opening O its gripping element II is in the slightly inclined position illustrated in Fig. 2 of the drawings and as the slip moves inwardly through contact with the wall of the tapered opening O the upper teeth 23 of the element I I have initial contact with the pipe P. As the slip S settles or moves downwardly in the opening O the element II rocks or swings so that the teeth 23 throughout its length come into engagement with the pipe P. The conditioning of the gripping element II by the spring 34 or by the insertion of the slip by means of the handle thus assures the initial engagement of the upper teeth 23 with the pipe P followed by the subsequent engagement of the other teeth with the pipe as the slip nds its place in the opening O. The means l2, therefore, prevents the gripping element II from improperly wedging against the pipe at the lower end of the element and assures the full extensive engagement of the gripping element with the pipe.

The gripping element H being free to shift or rock in the recess I8 may obtain extensive or complete engagement with the pipe P, even though the opening O may be worn out of round or the rotary table may not be truly horizontal. The gripping element Il is adapted to shift or rock in the recess I8 to have full proper gripping engagement with the pipe P under practically all operating conditions. It is to be understood that the several slips S embodied in the set of slips operate in the manner just described. The slips S are compact and light in weight and are easily handled. The automatically conditioned gripping elements li do not require any manual adjustment or manipulation and automatically align or position themselves for proper engagement with the pipe P when the slips are inserted in the opening O.

Figs. 5 and 6 of the drawings illustrate a form of the invention wherein each slip S comprises two connected body sections or bodies I@i adapted to be manipulated or handled by a single handle H. The bodies I@a of the slips S may be very similar to the above described body iii and carry gripping elements l la which may be identical with the gripping elements i I. Rods 22'@ similar to the rods 2'1 are connected with the gripping elements IIa and have heads 32zu on their upper ends. The two bodies ma comprising a slip S' are connected for limited relative movement to allow them to properly t in the bushing opening O. Lugs or vertically extending ribs iii project from adjacent sides of the bodies ia and have vertically spaced openings 4i. Pins 2 are shiftable in the openings ISI and have cotter keys 43, or the equivalent, for limiting relative lateral movement between the bodies IE!a of the slip S'. Springs 44 may be provided on the pins :i2 between the ribs lli] to yieldingly urge the bodies II)a apart.

'Ihe handle H of each slip S is provided for lifting and manipulating the slip. The handle H includes a loop-like head 36a and two stems 35a projecting inwardly from the head. rIhe inner ends of the stems EL are pivotally connected with the heads 32a. The heads 32a may be yoked and suitable pivot pins 3'Ia may pivotally connect the stems 35a with the heads 32a. The connections between the stems 35aL and the heads 32IL may have sufficient looseness to permit the desired relative movement between the sections or bodies lila. Springs 34a surround the rods 21a and are under compression between the heads 32a and washers 33a, to yieldingly urge or hold the gripping elements I Ia in their up or inclined positions. It will be apparent that lifting of Aa slip S by means of its handle H applies an upward force to the gripping elements Ila to definitely hold them in their up inclined positions.

The operation of the slips S illustrated in Figs. 5 and 6 of the drawings is substantially identical with the previously described form of the invention. The slips S' may be inserted in the opening O by means of the handles H. When the slips S are inserted in the opening O -by means of the handles H the outer surfaces of their` bodies IUEL engage the inclined wall of the opening and cause the toothed inner sides of the elements ila to come into contact with the pipe P. The elements I Ia are maintained in their up or inclined positions by the springs 34a and the lifting force exerted on the handles H and their up-per teeth first come into engagement with the pipe P. As the slips S settle or wedge in the l opening O the elements iIa swing or work until their teeth all come into proper gripping engagement with the pipe P. This prevents the gripping elements Iia from wedging against the pipe P at their lower ends and assuresV the dependable extensive engagement of the elements with the pipe.

Having described only typical preferred forms and applications of my invention, I do not wish to be limited or restricted to the specific details herein set forth, but wish to reserve to myself any variations or mo-diiications that may ap-pear to those skilled in the art or fall within the scope of the following claims.

Having described my invention, I claim:

1. A slip of the character described including, a body, a gripping element at the inner side of the body, cooperating surfaces on the body and element supporting the element for movement about a substantially horizontal axis, and means for urgingl the element to turn upwardly to present its portion above said axis for initial engagement with the object to be handled.

2. A slip of the character described including, a body having a recess in its inner side, a` gripping element cooperating with the wall of the recess to be shiftable in the recess about a substantially horizontal axis, and means for urging the element to turn upwardly to present its portion above said axis for initial contact with the object to be handled.

3. A slip of the character described including, a body having a recess in its inner side, a gripping element cooperating with the wall of the recess to be shiftable in the recess about a substantially horizontal axis, and a spring holding the element in a position where it presents its portion above said axis for initial contact with the object to be handled.

4. A slip of the character described including, a body having a recess in its inner side, a gripping element cooperating with the Wall of the recess to be shiftable in the recess about a substantially horizontal axis, and spring means acting upwardly on the element so that it presents its portion above said axis for initial contact with the object to be gripped.

5. A slip of the character described including,v

a body having a recess in its inner side, a gripping element cooperating with the wall of the recess to be shiftable in the recess about a substantially horizontal axis, and manual means for moving the element to present its portion above said axis for initial contact with the object to be gripped.

6. A slip of the character described including, a body having a recess in its inner side, a gripping element cooperating with the wall of the recess to be shiftable in the recess about a substantially horizontal axis, gripping means on the inner side of the element, and yielding means normally holding the element where it is inclined downwardly and outwardly to present the upper portion of the first named means for initial Contact with the object to be gripped.

'7. A slip of the character described including, a body having a recess in its inner side, a gripping element cooperating with the wall of the recess to be shiftable in the recess about a substantially horizontal axis, gripping means on the inner side of the element, and yielding means normally holding the element where it is inclined downwardly and outwardly to present the upper portion of the rst named means for initial contact with the object to be gripped, the yielding means including a spring bearing on the body, and an operative connection between the spring and element. l

8. A slip of the character described including, a body having a recess in its inner side, a gripping element cooperating with the wall of the recess to be shftable in the recess about a substantially horizontal axis, gripping means on the inner side of the element, and yielding means. normally holding the element where it is inclined downwardly and outwardly to present the upper portion of the iirst named means for initial contact with the object to be gripped, the yielding means including a rod pivotally connected with the element and a spring acting on the rod.

9. A slip of the character described including, a body having a recess in its inner side, a gripping element cooperating with the wall of the recess to be shiftable in the recess about a substantially horizontal axis, and manual means for moving the element to present its portion above said axis for initial contact with the object to be gripped, said means including a part connected with the element, and a handle connected with the said part.

10. A slip of the character described including, a body having a recess in its inner side, a gripping element cooperating with the wall of the recess to be shiftable in the recess about a substantially horizontal axis, means for limiting such shifting of the element, a handle for the body, and a connection between the handle and the element whereby lifting of the body by the handle moves the element to a downwardly and outwardly inclined position.

11. A slip of the character described including, a body having a recess in its inner side, a gripping element cooperating with the wall of the recess to be shiftable in the recess about a substantially horizontal axis, means for limiting such shifting of the element, a handle for the body, and a rod pivotally connected with the element and carrying the handle whereby the handle may be manipulated to rock the element.

12. A slip of the character described including, a body having a recess in its inner side, a gripping element cooperating with the wall of the recess to be shiftable in the recess about a substantially horizontal axis, a handle, a rod pivotally connected with the element and connected with the handle whereby the handle may be manipulated to rock the element, and spring means normally urging the element upwardly.

13. A slip of the character described including, a body having a recess in its inner side, a gripping element cooperating with the wall of the recess to be shiftable in the recess about a substantiallyl horizontal axis, a handle, a rod pivotally connected with the element and connected 'with the handle whereby the handle may be manipulated to rock the element, and a spring acting on the rodV to urge the element upwardly.

14. A slip including, two connected body sections each having a recess in its inner side, a pipe gripping element in each recess cooperating with the wall thereof to rock about a substantially horizontal axis, a handle for the sections, and connections between the handle and elements whereby the handle may be manipulated to rock the elements.

15. A slip including, two connected body sections each having a recess in its inner side, a' pipe gripping element in each recess cooperating with the Wall thereof to rock about a substantially horizontal axis, a handle for the sections, and members connecting the handle'with the elements, and springs acting on the members to urge K the elements upwardly. 

